This invention generally relates to a warning system for indicating the wear condition of brake linings. More particularly, but not by way of limitation, this invention relates generally to a warning system for indicating the wear conditions of liquid cooled brakes such as those used in heavy off road type vehicles.
Brake systems utilized in heavy off road vehicles are subjected to a substantial amount of wear due to the frequent starting and stopping and the changing of directions of the vehicle. Brake systems that are liquid cooled, are relatively complex to disassemble and reassemble to check the condition of the brakes. It requires substantial time and effort to make such checks. Accordingly, it is highly desirable to be able to provide a brake wear condition indicating system that remotely indicates the condition of the brakes without the necessitating the disassembly of the brake system.
Many attempts have been made in an effort to indicate the brake wear condition from a remote location. Among those is the system described in U.S. Pat. No. 1,690,121 issued Nov. 6, 1928 to A. Klimk. The system described therein displaces liquid from a cylinder as the brake bands wear. The liquid is piped to a remote location and is connected with an indicator which shows the brake wear condition.
An electrical or light system for indicating brake wear condition is described in U.S. Pat. No. 4,184,145, issued Jan. 15, 1980, to a Raoul G. Fima. Systems utilizing pneumatic signals are illustrated in U.S Pat. No. 3,593,266 issued July 13, 1971, to John K. Van Sickle and U.S. Pat. No. 4,201,974, issued May 6, 1980 to Raoul G. Fima.
U.S. Pat. No. 4,186,822, issued Feb. 5, 1982, to Natabara Khuntia describes a mechanical system for indicating the condition of the brakes. The system utilizes a hole formed in the brake housing (with removable plug) through which a measurement can be made to ascertain the wear condition. The measurement is made through the hole from a known surface within the brake system to the exterior of the housing at the hole. It is necessary to mechanically measure each brake but the system is an improvement over totally disassembling a very complex, liquid cooled brake system.
An object of this invention is to eliminate the necessity for disassembling of the brake system and to eliminate the necessity for mechanical measurement to ascertain the wear condition of the brakes of a vehicle.